Alert archive / South Carolina
Weather alerts in South Carolina, 2013
3,080 weather alerts in 2013, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered any part of the state, so the counties below add up to more than the state.
Weather alerts by county
Each county as a circle sized by its count in 2013. Tap one for its archive.
- Alerts
- 3,080
- Warnings
- 902
- Watches
- 91
- Advisories
- 914
- Busiest month
- July797 alerts
- Busiest day
- July 12, 201378 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
5 of 27 tornado warnings covering South Carolina in 2013 had a tornado report inside them; 8 of 10 tornado reports fell inside a warning, on average 11 minutes after it went out.
South Carolina, 2013
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 27 | 5 | 81% | 10 | 80% | 11 min |
| Severe thunderstorm warnings | 378 | 278 | 26% | 566 | 84% | 24 min |
| Flash flood warnings | 81 | 60 | 26% | 212 | 89% | 84 min |
Each office's whole area, 2013
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Greenville-Spartanburg, SC: tornado warnings | 11 | 3 | 73% | 6 | 83% | 14 min |
| NWS Greenville-Spartanburg, SC: severe thunderstorm warnings | 340 | 240 | 29% | 467 | 86% | 24 min |
| NWS Greenville-Spartanburg, SC: flash flood warnings | 91 | 69 | 24% | 204 | 81% | 68 min |
| NWS Wilmington, NC: tornado warnings | 7 | 1 | 86% | 1 | 100% | 5 min |
| NWS Wilmington, NC: severe thunderstorm warnings | 65 | 42 | 35% | 115 | 66% | 26 min |
| NWS Charleston, SC: tornado warnings | 15 | 1 | 93% | 3 | 67% | 10 min |
| NWS Charleston, SC: severe thunderstorm warnings | 132 | 79 | 40% | 271 | 81% | 25 min |
| NWS Charleston, SC: flash flood warnings | 44 | 32 | 27% | 154 | 92% | 116 min |
| NWS Columbia, SC: tornado warnings | 5 | 2 | 60% | 3 | 67% | 6 min |
| NWS Columbia, SC: severe thunderstorm warnings | 98 | 80 | 18% | 169 | 88% | 24 min |
| NWS Columbia, SC: flash flood warnings | 21 | 12 | 43% | 33 | 79% | 43 min |
An office's figures cover every county it serves, including across state lines.
Verified by the Iowa Environmental Mesonet's Cow, which matches each storm-based warning with the local storm reports inside its polygon while it was in force, within 15 km of its edge: a tornado warning counts as verified on a tornado report, a severe thunderstorm warning on hail of 1 inch or more, a gust of 58 mph or more, or wind damage, a flash flood warning on a flash flood report. The false alarm ratio is the share of warnings with no such report; "inside a warning" is the probability of detection, the share of reports that fell inside one; lead time runs from the warning's issue to each report inside it, counting zero for a report that came first. A warning with no report is not proof nothing happened: reports come from spotters, the public and damage surveys, and are thin where few people live.
The alerts
3,080 alerts are too many to list on one page. Narrow it to a product above, to a month in the chart, or to a county.
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Berkeley County287
- Richland County214
- Greenville County202
- Lexington County200
- Colleton County199
- Anderson County197
- Charleston County193
- Dorchester County184
- Spartanburg County173
- Horry County170
- Hampton County163
- Aiken County161
- Calhoun County157
- Florence County152
- Pickens County151
- Laurens County150
- Oconee County148
- Cherokee County147
- York County147
- Marion County146
- Kershaw County143
- Fairfield County138
- Williamsburg County137
- Sumter County135
- Georgetown County135
- Clarendon County134
- Chester County134
- Union County132
- Jasper County131
- Newberry County130
- Barnwell County124
- McCormick County122
- Allendale County122
- Dillon County122
- Edgefield County119
- Abbeville County116
- Chesterfield County112
- Greenwood County112
- Marlboro County112
- Lee County110
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordThe radar archive20122014
Sources
National Weather Service watches, warnings, advisories and statements from the Iowa Environmental Mesonet's VTEC archive, which reconstructs tornado, severe thunderstorm, flash flood and marine warnings back to 1986 from the NWS text archive. Storm Prediction Center watches and mesoscale discussions from SPC's archive through the Mesonet. County centers from the US Census Bureau. Warning verification from the Mesonet's Cow. Rebuilt daily.